route-rs

This crate is my attempt at a safe helper for mapping URL routes to handlers for rust web applications.

There are several routing libraries already available, but all of the ones I have been able to find share a common problem: path patterns are defined as strings, and URL parameters get parsed out at runtime and stashed in some kind of Map that handlers have to .get() and .unwrap() to access. I want to extract parameters without unwrapping, and I want rust's type system to ensure that I'm not making mistakes!

Setup

in Cargo.toml:

[dependencies]
route = "0.2.0"

route just exports a the macro route!, so you need to #[macro use] it:

#[macro use]
extern crate route;

Usage

Suppose you have some HTTP request/response server setup like

// imaginary request/response structs provided by the framework:

struct Request<'a> {
    path: &'a str,
}

type Response = String;


// application handlers that we need to route:
// Note that some handlers take extra parameters that we hope to fill from the path!

fn home(req: &Request) -> Response {
    "home".to_string()
}

fn blog_post(req: &Request, id: u32) -> Response {
    format!("blog: {}", id)
}

fn account(req: &Request, subpath: &str) -> Response {
    format!("account -- subpath: {}", subpath)
}

Then you could set up a routing handler like:

fn handle_route(req: &Request) -> Response {
    route!(req.path, {
        (/)                 => home(req);
        (/"blog"/[id: u32]) => blog_post(req, id);
        (/"me"[/rest..])    => account(req, rest);
    });
    Response::from("not found")
}

And you're set!

assert_eq!(handle_route(&Request { path: "/" }),
    Response::from("home"));

assert_eq!(handle_route(&Request { path: "/blog/42" }),
    Response::from("blog: 42"));

assert_eq!(handle_route(&Request { path: "/me/a/b/c" }),
    Response::from("account -- subpath: /a/b/c"));

assert_eq!(handle_route(&Request { path: "/foo" }),
    Response::from("not found"));